# gst: the fascinating possibility of two black holes masquerading as one.

<< a pair of black holes whose mutual attraction is balanced by the cosmic expansion would look the same to a distant observer as a single isolated black hole. >>

Oscar J.C. Dias and coll. << point out that when the black holes are allowed to rotate, it is possible that their spin interaction may stabilize the solutions. This raises the fascinating possibility of having an isolated pair of solar-mass black holes in our Universe, balancing happily a few hundred light years apart and impossible to distinguish from a single black hole from far away. >>

<< If these black holes are set up in precisely the correct way, they sit in an unstable equilibrium, akin to a pen balanced on its pointed end. Any disturbance will ruin this perfect balance. >>

Toby Wiseman. Two Black Holes Masquerading as One. Physics 16, 164. Sep 25, 2023. 

https://physics.aps.org/articles/v16/164

Oscar J. C. Dias, Gary W. Gibbons, et al. Static Black Binaries in de Sitter Space. Phys. Rev. Lett. 131, 131401. Sep 25, 2023.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.131401

Also: black hole, astrophysics, in: https://www.inkgmr.net/kwrds.html 

Keywords: gst, black hole, astrophysics

# life: simnotrelvir, a Chinese pill anti covid-19

<< A drug called simnotrelvir speeds up recovery from mild to moderate COVID-19 by about 1.5 days, relieving symptoms such as fever, cough and runny nose.  >>

<< Whether it can help people who are at high risk of hospitalization and death from COVID-19 is still unclear. >>️️

Saima Sidik. Potent new pill provides COVID relief for the masses. Nature. doi: 10.1038/d41586-024-00117-5. Jan 17,  2024. 

https://www.nature.com/articles/d41586-024-00117-5

Bin Cao, Yeming Wang, et al. Oral Simnotrelvir for Adult Patients with Mild-to-Moderate Covid-19. N Engl J Med 2024; 390:230-241. doi: 10.1056/NEJMoa2301425. Jan 18, 2024.

https://www.nejm.org/doi/10.1056/NEJMoa2301425

FonT: if it is (another) 'pastroky', you can redirect yourself towards an alcohol plus peroxide solution... just to put the classic patch on it. 

Also:  a proposito di '1or2achoos' (da Wuhan (?)), qui la cronologia. FonT. Oct 4, 2023. 

https://flashontrack.blogspot.com/2023/10/life-proposito-di-1or2achoos-da-wuhan.html

Also: 1or2achoos, sars, covid, virus, pastroky, in:   https://www.inkgmr.net/kwrds.html

Keywords: life, virus, flu, coronavirus,  sarscov2, covid19, 1or2achoos, mask

# gst: pseudo epileptic seizures in self-organized bistability

<< Self-organized bistability (SOB) stands as a critical behavior for the systems delicately adjusting themselves to the brink of bistability, characterized by a first-order transition. >>️

(AA) << embark on a theoretical exploration that extends the boundaries of the SOB concept on a higher-order network (implicitly embedded microscopically within a simplicial complex) while considering the limitations imposed by coupling constraints. >>️

AA << use continuous synchronization diagrams and statistical data from spontaneous synchronized events to demonstrate the crucial role SOB plays in initiating and terminating temporary synchronized events. (They) show that under weak coupling consumption, these spontaneous occurrences closely resemble the statistical traits of the epileptic brain functioning. >>

️

Md Sayeed Anwar, Nikita Frolov, Alexander E. Hramov, Dibakar Ghosh. Self-organized bistability on globally coupled higher-order networks. arXiv: 2401.02825v1 [nlin.AO]. Jan 5, 2024.

https://arxiv.org/abs/2401.02825

Also: transition, self-assembly, brain, in: https://www.inkgmr.net/kwrds.html

Keywords: gst, transition, self-assembly, bistability, self-organized bistability, brain, epileptic seizure

# gst: correlated noise and critical dimensions.

<< In equilibrium, the Mermin-Wagner theorem prohibits the continuous symmetry breaking for all dimensions d≤2. In this work, (AA) discuss that this limitation can be circumvented in nonequilibrium systems driven by the spatiotemporally long-range anticorrelated noise. >>

<< results suggest that the critical dimensions increase when the noise is positively correlated in space and time and decrease when anticorrelated. (AA)  also report that the spherical model with the correlated noise shows the hyperuniformity and giant number fluctuation even well above the critical point. >>️

Harukuni Ikeda. Correlated noise and critical dimensions. Phys. Rev. E 108, 064119. Dec 13, 2023.

https://journals.aps.org/pre/abstract/10.1103/PhysRevE.108.064119 

Also: noise, fluctuations, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, noise, fluctuations

# gst: pulsating active matter.

<< the mechanical pulsation of locally synchronized particles is a generic route to propagate deformation waves. >>

️

AA << consider a model of dense repulsive particles whose activity drives periodic change in size of each individual. >>️

They << show that the competition between repulsion and synchronization triggers an instability which promotes a wealth of dynamical patterns, ranging from spiral waves to defect turbulence. >>️

Yiwei Zhang, Etienne Fodor. Pulsating Active Matter. Phys. Rev. Lett. 131, 238302. Dec 8, 2023. 

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.238302

Also: waves, particle, transition, instability, turbulence, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, waves, particle, transition, instability, turbulence

# gst: scanning inside a granular raft

<< Rheology of macroscopic particle-laden interfaces, called “granular rafts,” has been experimentally studied in the simple shear configuration.  >>️

<< Close to the walls of the rheometer cell, one can observe regions of large local shear rate while in the middle of the cell a quasistatic zone exists. >>

<< Measuring the probability density functions of the instantaneous local shear rate, (AA) provide evidence of a balance between positive and negative instantaneous local shear rate. This behavior is the signature of a quasistatic region inside the granular raft. >>️

️

J. Lalieu, A. Seguin, G. Gauthier. Rheology of granular rafts. Phys. Rev. E 107, 064901. June 29, 2023.

https://journals.aps.org/pre/abstract/10.1103/PhysRevE.107.064901

Also: Bavand Keshavarz, Michela Geri. Mandelbrot granular raft. Phys. Rev. Fluids 8, 110506. Nov 16, 2023.

https://journals.aps.org/prfluids/abstract/10.1103/PhysRevFluids.8.110506

Also: grain, particle, in https://www.inkgmr.net/kwrds.html 

Also: << l'invasiva scorribanda /

sull' oramai alla deriva lacerata randa. >>️ in: Schismi da vibrati di tangone. Notes. March 23, 2005. (quasi-stochastic poetry)

https://inkpi.blogspot.com/2005/03/1608b-schismi-da-vibrati-di-tangone.html

Keywords: gst, raft, particle, grain, granular raft, life

# gst: buckling instability of sticky bubbles.

<< A slender object undergoing an axial compression will buckle to alleviate the stress. Typically the morphology of the deformed object depends on the bending stiffness for solids, or the viscoelastic properties for liquid threads. >>️

AA << study a chain of uniform sticky air bubbles in an aqueous bath that rise due to buoyancy. A buckling instability of the bubble chain, with a characteristic wavelength, is observed in the absence of a bending stiffness. If a chain of bubbles is produced faster than it is able to rise, the dominance of viscous drag over buoyancy results in a compressive stress that is alleviated by buckling the bubble chain. >>

️

Carmen L. Lee, Kari Dalnoki-Veress. Buckling instability in a chain of sticky bubbles. arXiv: 2311.15452v1 [cond-mat.soft]. Nov 26, 2023.

https://arxiv.org/abs/2311.15452

Also: bubble, instability, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, bubble, instability, buckling instability